ABSTRACT Sourgrass (Digitaria insularis) is one of the principal weeds in Brazil, and there are reports of its being glyphosate-resistant. The aim of this study was to determine the coexistence period of the TMG7063 IPRO soybean cultivar with a weed community predominated by D. Insularis, with no negative interference on final production (period prior to interference - PPI), as well as to determine the period for which the crop might remain free of such interference (total period of interference prevention) in Brazil. The coexistence and control periods under study were 15, 30, 45, 60, 75, 90, 105, and 120 days after sowing (DAS) the soybean, with the experiment arranged in a randomized block design with four replications. At the end of each coexistence period and at the end of the control-period experiment (single collection), there was an increase in weed density, dry matter, and the relative importance of D. insularis as the coexistence period increased. The number of pods was reduced from 87 (from 120 DAS in the control) to 49 (from 75 DAS for coexistence), and maximum yield was reduced from 5,551.3 kg ha-1 (from 120 DAS in the control) to 3,998.6 kg ha-1 (from 60 DAS for coexistence) due to coexistence with the weed community. The PPI was estimated at nine DAS, with losses of 5.0%. It can be concluded that a weed community predominated by D. insularis reduces soybean yield by up to 59.3%. The ‘TMG 7063 IPRO’ soybean can coexist with a weed community predominated by D. insularis for up to nine days after sowing and tolerate a loss in yield of up to 5%. Digitaria Brazil glyphosateresistant. glyphosateresistant glyphosate resistant. resistant glyphosate-resistant TMG TMG706 D Insularis PPI, , PPI) total prevention 15 30 45 90 105 12 (DAS replications controlperiod single collection, collection collection) density matter increased 8 4 7 coexistence, 55513 5 551 3 5,551. ha1 ha 1 ha- 39986 998 6 3,998. 50 0 5.0% 593 59 59.3% 706 5% TMG70 9 10 5551 55 5,551 3998 99 3,998 5.0 59.3 70 TMG7 555 5,55 399 3,99 5. 59. 5,5 39 3,9 5, 3,

RESUMO Physalis angulata é uma Solanaceae, que produz frutos de alto valor comercial. A interferência de plantas daninhas no cultivo dessa espécie é um dos principais fatores limitantes e não há herbicidas registrados. O objetivo deste estudo foi avaliar a seletividade de herbicidas e o uso de adjuvantes no cultivo de P. angulata. Foram conduzidos três experimentos: dois em vasos, avaliando a seletividade dos herbicidas fluazifop-p-butílico, metribuzim, fomesafem+fluazifop-p-butílico, trifluralina e cletodim; e um a campo, com os herbicidas mais seletivos dos ensaios anteriores. Em vaso, foram realizadas avaliações visuais de fitotoxicidade, além da altura das plantas, diâmetro do caule e teor de clorofila, a cada 7 dias, até os 42 dias após aplicação. Ao término dos três experimentos, além dessas características, foram avaliados a área foliar, número de frutos e massa seca de folhas, caule e frutos. Os herbicidas clethodim sem adjuvante e fluazifop-p-butil são seletivos para P. angulata. Em condições de campo, a aplicação de fluazifop-p-butil + fomesafen não afetou negativamente a produtividade e o crescimento da cultura, sendo seletivo a P. angulata. O metribuzin não demonstrou potencial para ser utilizado nesta cultura.

ABSTRACT Physalis angulata is a Solanaceae that produces fruits with a high commercial value. The interference of weeds in the cultivation of this species is one of the main factors limiting its growth. There are no herbicides registered for this crop in Brazil. Thus, the objective of this study was to evaluate the selectivity of herbicides and the use of adjuvants for the cultivation of P. angulata. We conducted three experiments: two in pots, evaluating the selectivity of the herbicides fluazifop-p-butyl, metribuzin, fomesafen + fluazifop-p-butyl, trifluralin and clethodim; and one in field conditions using the most selective herbicides from previous experiments. In the pots, we performed assessments of phytotoxicity, height, stem diameter, and total chlorophyll content every seven days up to 42 days after application. At the end of the three experiments, we evaluated leaf area, number of fruits, and dry matter of leaves, stems, and fruits. The herbicides clethodim without adjuvant and fluazifop-p-butyl are selective for P. angulata crop. Under field conditions, the application of fluazifop-p-butyl + fomesafen did not negatively affect crop production and growth, being selective to P. angulata. Metribuzin do not have the potential to be used for this crop.

Abstract Water deficit is considered the most critical environmental factor for peanut production in Brazil, as it constitutes one of the major constraints to the expansion of its cultivation in the suitable crop zones of the country. Determining crop water demand is fundamental to increasing yield with lower water consumption. The present study aimed to evaluate the effects of full and deficit irrigation levels (L1 = 8%, L2 = 27%, L3 = 63%, L4 = 94% and L5 = 100% replenishment of crop evapotranspiration) on the development, growth and yield of peanut crop sown in two times, February and March. Treatments were distributed in a split-plot randomized complete block design, with four replicates, using a line-source sprinkler system. Irrigation depths from 65 to 314 mm were applied with the levels L1 to L5 during the first and second cropping cycles. Full irrigation with sowing in March was more advantageous due to yield increase of up to 30% compared to sowing in February, but crop cycle was 25 days longer. Water stress caused by deficit irrigation reduced plant height, seed mass and pod yield, while full irrigation (L5) led to yields from 4,141 to 5,102 kg ha-1 for February and March, approximately three times higher than those obtained with the lowest irrigation level (L1).

Resumen El déficit de agua se considera el factor ambiental más crítico para la producción de maní en Brasil, ya que constituye una de las principales limitaciones para su expansión en las zonas adecuadas para su cultivo en el país. Determinar la demanda de agua de los cultivos es fundamental para aumentar el rendimiento con un menor consumo de agua. El presente estudio tuvo como objetivo evaluar los efectos de los niveles de riego deficitarios y completos (L1 = 8%, L2 = 27%, L3 = 63%, L4 = 94% y L5 = 100% de reposición de la evapo transpiración del cultivo) en el desarrollo, crecimiento y rendimiento de la cosecha de maní sembrado en dos veces, febrero y marzo. Los tratamientos se distribuyeron en un diseño de bloques completos aleatorios de parcelas divididas, con cuatro repeticiones y utilizando un sistema de aspersores de fuente de línea. Las láminas de riego aplicadas fueron entre 65 a 314 mm (L1 a L5) en ambos ciclos de cultivo. El nivel de riego total con siembra en marzo fue más ventajoso debido al aumento del rendimiento de hasta un 30% en comparación con la siembra en febrero, pero el ciclo de cultivo fue 25 días más largo. El estrés hídrico causado por el riego deficitario redujo la altura de la planta, la masa de semillas y el rendimiento de vainas. El cultivo de maní con riego completo (L5) tuvo rendimientos de 4,141 a 5,102 kg ha-1 (febrero y marzo respectivamente) siendo aproximadamente tres veces más que los obtenidos con el nivel de riego deficitario más bajo (L1).

RESUMO: Objetivou-se determinar os períodos de interferência da mucuna-preta na soqueira cana-de-açúcar, cultivar 'RB855536', e o potencial de redução na produtividade da cultura e na qualidade do produto colhido. Foi utilizado o delineamento experimental em blocos casualizados, com quatro repetições por tratamento, aplicando-se 18 tratamentos divididos em dois grupos. No primeiro, a cultura permaneceu livre da interferência da mucuna-preta desde a brotação até nove épocas do seu ciclo de vida: 0-15, 0-30, 0-45, 0-60, 0-90, 0-120, 0-150, 0-180 dias após a brotação (DAB), 0-colheita. No segundo grupo, a cultura permaneceu em convivência com a mucuna-preta desde a brotação até os mesmos períodos descritos anteriormente. O período crítico de prevenção à interferência da mucuna-preta na soqueira da cultura da cana-de-açúcar ´RB 855536´ abrangeu 138 dias do ciclo da cultura, de 50 DAB (PAI) a 188 DAB (PTPI). E a redução da produtividade da cana-de-açúcar em decorrência da interferência da mucuna-preta foi de 50%, afetando negativamente a qualidade do produto colhido.

ABSTRACT: The objective of the present study was to determine the periods of interference of velvet bean on ratoons of sugarcane cultivar 'RB855536' and to identify its potential for decreasing the crop yield and the quality of the harvested product. The experiment was arranged in a randomized block design, with 18 treatments divided into two groups and four replicates per treatment. In the first group, the sugarcane was kept free from velvet bean interference for nine different periods, beginning at bud sprouting: 0-15, 0-30, 0-45, 0-60, 0-90, 0-120, 0-150, and 0-180 days after budding (DAB) and 0-harvest. In the second group, sugarcane was grown in coexistence with velvet bean during the same periods described for the first group. The critical period of interference prevention for velvet bean in ratoons of sugarcane cv. 'RB 855536' lasted 138 days, from 50 DAB (pre-interference period [PIP]) to188 DAB (total period of weed interference prevention [TPIP]). Velvet bean interference caused a 50% decrease in sugarcane yield and negatively affected the quality of the harvested product.